Effects of Kappa Bungarotoxin on Avoidance Learning and Spatial Memory Abilities in Mice

おおappa bungarotoxin(KBGT,3 25μg/kg) microinjected into hippocampal of mice impaired avoidance learning and memory abilities.On the 4th training day,the avoidance latency decreased by 58 3% and 16 7% respectively in the control group and K BGT group compared with those relevant parameters on the lst training day.On the last training day ,there were 80% mice in the control group found the platform underwater,while there were only 33 3% mice in K BGT group found the platform in 60 times tests within the fixed time.On the sixth day when the platform was removed,the mean numbers of mice swimming across the location areas where the platform was originally placed in the control group was 5 3±28, whereas the same parameter in K BGT was 1 9±1 2.In the step through test, the latency in K BGT group decreased by 38 3% and the rate of errors within 5 min increased 2 25 folds compared with the control group.At the dose of 40mg/kg,lecithin had no improving effects on the avoidance learning and spatial memory abilities in normal mice on 14 day oral administration,but improved the learning and memory abilities in mice impaired by K BGT.